1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
/*
Copyright (c) 2011 Red Hat Incorporated.
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
The name of Red Hat Incorporated may not be used to endorse
or promote products derived from this software without specific
prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL RED HAT INCORPORATED BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
; clobberable
r8 = 0xffef0
r9 = 0xffef1
r10 = 0xffef2
r11 = 0xffef3
r12 = 0xffef4
r13 = 0xffef5
r14 = 0xffef6
r15 = 0xffef7
; preserved
r16 = 0xffee8
r17 = 0xffee9
r18 = 0xffeea
r19 = 0xffeeb
r20 = 0xffeec
r21 = 0xffeed
r22 = 0xffeee
r23 = 0xffeef
/* The jump buffer has the following structure:
R0 .. R23 3*8 bytes
SP 2 bytes
ES 1 byte
CS 1 byte
PC 4 bytes
*/
#define SAVEB(ofs,reg) mov a,reg | mov [hl+ofs],a
#define SAVE(ofs,reg) movw ax,reg | movw [hl+ofs],ax
.global _setjmp
.type _setjmp, @function
_setjmp:
;; R8 = setjmp (jmp_buf *[sp+4].w)
;; must return zero !!
push ax
push hl
push ax
movw ax, [sp+10]
movw hl, ax
pop ax
movw [hl], ax
SAVE (2, bc)
SAVE (4, de)
pop ax
movw [hl+6], ax
SAVE (8, r8)
SAVE (10, r10)
SAVE (12, r12)
SAVE (14, r14)
SAVE (16, r16)
SAVE (18, r18)
SAVE (20, r20)
SAVE (22, r22)
;; The sp we have now includes one more pushed reg, plus $PC
movw ax, sp
addw ax, #6
movw [hl+24], ax
SAVEB (26, es)
SAVEB (27, cs)
SAVE (28, [sp+2])
SAVE (30, [sp+4])
clrw ax
movw r8, ax
pop ax
ret
.size _setjmp, . - _setjmp
#define LOADB(ofs,reg) mov a,[hl+ofs] | mov reg,a
#define LOAD(ofs,reg) movw ax,[hl+ofs] | movw reg,ax
#define PUSH(ofs) movw ax,[hl+ofs] | push ax
.global _longjmp
.type _longjmp, @function
_longjmp:
;; noreturn longjmp (jmp_buf *[sp+4].w, int [sp+6].w)
movw ax, [sp+6]
cmpw ax,#0
sknz
onew ax
movw r8, ax
movw ax, [sp+4]
movw hl, ax
movw ax, [hl+24]
movw sp, ax ; this is the *new* stack
PUSH (30) ; high half of PC
PUSH (28) ; low half of PC
PUSH (6) ; HL
PUSH (0) ; AX
LOAD (2, bc)
LOAD (4, de)
LOAD (10, r10)
LOAD (12, r12)
LOAD (14, r14)
LOAD (16, r16)
LOAD (18, r18)
LOAD (20, r20)
LOAD (22, r22)
LOADB (26, es)
LOADB (27, cs)
pop ax
pop hl
ret ; pops PC (4 bytes)
.size _longjmp, . - _longjmp
|
